A Collaborative Defense Against Wear Out Attacks in Non-Volatile Processors

While the Internet of Things (IoT) keeps advancing, its full adoption is continually blocked by power delivery problems. One promising solution is Non-Volatile (NV) processors, which harvest energy for themselves and employ a NV memory hierarchy. This allows them to perform computations when power is available, checkpoint and hibernate when power is scarce, and resume their work at a later time. However, utilizing NV memory creates new security vulnerabilities in the form of wear out attacks in the register file. This paper explores the dangers of this design oversight and proposes a mitigation strategy that takes advantage of the unique properties and operating characteristics of NV processors. The proposed defense integrates the power management unit and a two-level register rotation approach, which improves NV processor endurance by 30.1× in attack situations and an average of 7.1× in standard workloads.